Some optical systems, such as Wavelength Division Multiplexing (WDM) systems, transmit and receive modulated optical signals over optical fibers. Various techniques for allocating wavelength to optical carriers are known in the art.
For example, U.S. Patent Application Publication 2005/0244161, whose disclosure is incorporated herein by reference, describes an optical transmission system in which a transmission section outputs plural monochromatic-wavelength lights individually, a first allocation section allocates a wavelength of a monochromatic-wavelength light based on a power of the monochromatic-wavelength light individually outputted from the transmission section from among the plural monochromatic-wavelength lights, a notification section issues a notification of wavelength information of the monochromatic-wavelength lights allocated by the first allocation section to the transmission section, and a first control section controls wavelengths of the monochromatic-wavelength lights to be outputted from the transmission section based on the wavelength information of the notification issued from the notification section.
As another example, U.S. Pat. No. 7,720,384, whose disclosure is incorporated herein by reference, describes a transponder in a WDM apparatus, which detects a wavelength of received light having one of plural wavelengths multiplexed or divided by a WDM unit, determines a transmission wavelength which is a wavelength of a light to be transmitted to the WDM unit on the basis of the wavelength of the received light, and sets to convert the wavelength of the light to be transmitted to the WDM unit into the transmission wavelength, and transmit the converted light.